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本文根据1990年9月～1992年10月所作的调查,描述了斯里兰卡西北省普塔勒姆/Mundel河口系统的渔业生产和鱼类资源。普塔勒姆泻湖和Mundel湖渔业生产的特点是物种繁多、捕捞工具多样。大约1700只渔船所使用的渔具有浮动刺网、底网、三层刺网、拖网和围网,主要捕捞有鳍鱼类和甲壳动物类资源。此外,在浅水区还广泛使用各种推网、拉网和拖网。在普塔勒姆泻湖中还使用诱捕装置捕捉泥蟹。大约50%的渔船装备有船外马达,其它50%则是传统的木舟和木筏。捕捞活动在连接普塔勒姆泻湖和Mundel湖的Dutch运河也很集中。这两个水域的捕捞活动全年都在进行,但在西南季风期间(即5～9月),由于公海风大浪高,可以看到这时的捕捞活动有所增加。在此期间,通常在公海从事渔业生产的渔民,将捕捞场所转移到了河口系统。在过去10年间,河口系统中机动渔船的捕捞活动大大增加了。配备着尼龙刺网和三层刺网的玻璃钢(FRP)船是主要的渔船/渔具组合。对于刺网,这种组合形式的捕获率每次约为18kg,若用三层刺网,每次为12kg。据估计,该河口系统总的年捕获量1991年为5117t,1992年为2967t。产量下降的主要原因是鱼类储量的减少,在某种程度上也是捕捞活动下降及改变的结果。对普塔勒姆泻湖和Mundel湖渔业生产所作的生物经济评价表明,捕捞活动至少应分别减少20%和50%,或者加大鱼网的网眼。看来,在Mundel湖使用拖网,以及在普塔勒姆泻湖使用牵网和推网造成了很大的环境破坏。基于这些结果,本文相应提出了一些管理上的建议。
Based on a survey conducted between September 1990 and October 1992, the paper described fisheries production and fish stocks at the Putalim / Mundel Estuary system in Northwestern Sri Lanka. The characteristics of the fishing production at Putallam Lagoon and Mundel Lake are diverse and diverse fishing tools. About 1,700 fishing vessels are used fishing nets floating net, the bottom net, three gillnets, trawls and the fence, the main catch of finfish and crustacean resources. In addition, various push nets, pull nets and trawls are also widely used in shallow water areas. Traps are also used to catch mud crabs in Putalham Lagoon. About 50% of fishing vessels are equipped with outboard motors, while the other 50% are traditional canoes and rafts. Fishing is also concentrated on the Dutch Canal connecting Puttalam and Mundel Lakes. Fishing activities in these two waters are conducted all year round. However, during the southwest monsoon (ie May-September), the fishing activities at this time have been increased due to the storms on the high seas. During this period, fishers, often engaged in fishery production on the high seas, shifted the fishing grounds to estuarine systems. The fishing activities of motorized fishing vessels in estuarine systems have greatly increased over the past decade. Fiberglass (FRP) boats equipped with nylon gill nets and triple gill nets are the main fishing boat / gear combinations. For gill nets, the capture rate for this combination is about 18kg each time, with three gill nets each 12kg. It is estimated that the total annual catch of the estuarine system was 5117 tons in 1991 and 2967 tons in 1992. The main reason for the decline in production is the reduction of fish stocks, to a certain extent, the result of declines and changes in fishing activities. The bioeconomic evaluation of fishing production at the Putallam Lagoon and Mundel Lake shows that fishing activities should be reduced by at least 20% and 50% respectively, or that fishing nets should be enlarged. It appears that the use of trawls at Lake Mundel and the use of entrails and push screens at Puttalam lagoons have caused considerable environmental damage. Based on these results, this paper put forward some management suggestions.